The aforementioned U.S. Pat. No. 5,163,516 describes a fire fighting system for a chimney or wood burning stove fire that is out of control. The fire fighting system dumps chemical fire extinguishing materials upon an out-of-control chimney fire in sequential or multistage increments.
In theory, such dumping is a more efficient means of bringing these raging fires under control than is bulk application of the chemicals. The various compounds of the extinguisher of the aforementioned patent are encased and nested in a fusible, time-release membrane. The staged release of the chemicals incrementally brings the fire under control.
In practice, however, the staging of the extinguisher chemicals is not always uniformly accomplished. It has been discovered that the fusible membranes housing the chemicals may often rupture due to the formation of hot spots and consequential partial burn-through that occur in the fuse cap. When this happens, the chemicals will gradually leak out of their membranes over time, causing the fire-fighting system to become ineffective.
It would be advantageous to provide an improved combination of fuse cap and charge-containing members that prevents the formation of hot spots in the fuse cap. The possibility of chemical leakage would therefore be greatly reduced, thus maintaining the integrity of the chemical storage system.